The present invention relates vehicle accessory equipment, and more particularly, to an apparatus for detecting the angle of inclination of a vehicle and for providing an alarm signal when the inclination of the vehicle exceeds a predetermined safety limit.
In recent years, the driving of automotive type vehicles over rough terrain has increased substantially, both as a form of recreation and in connection with work in remote areas. In the offroad vehicle sport, trucks, JEEP brand vehicles, and other powered automotive type vehicles are frequently driven over steeply inclined terrain. As a safety precaution, most of these offroad vehicles are equipped with roll bars and seat belts to protect the passengers if the vehicle should roll. In addition, a number of inclinometers have been available for use in offroad vehicles to provide the driver with an indication of the degree to which his or her vehicle is inclined so that the driver will not exceed the safe limit of inclination of the vehicle.
A first one of the aforementioned available inclinometers comprises a glass tube with a ball bearing and colored water therein. The glass tube has indicia in the form of degree markings. A second one of these inclinometers is sometimes referred to as a tilt and grade indicator. Two tiny facsimiles of an offroad vehicle are secured to the lower ends of corresponding pendulums which rotate around horizontal axes. The tiny vehicle facsimiles rotate adjacent protractor-like panels to provide an indication of the degree of inclination. In a third type of inclinometer which has been available for use in offroad vehicles, a ball with degree markings thereon is buoyantly supported in a fluid and is enclosed within a transparent container. As the vehicle tips, the angle of inclination can be read off of the floating ball.
The aforementioned inclinometers are typically mounted on the dashboard of an offroad vehicle. Their use requires that the driver repeatedly observe them to obtain a reading of the angle of inclination of the vehicle. This can be dangerous since driving over rough terrain requires the full attention of the driver. The driver should always watch where he or she is going and should not look away at some device mounted on the dashboard. Furthermore, the aforementioned inclinometers are not very accurate. Typically, an offroad vehicle experiences substantial bumping and jerking motion. This can cause inclinometers of the aforementioned type to give false readings. Finally, the aforementioned inclinometers require that the driver be constantly aware of the safe degree of inclination of his or her vehicle so that the reading given by the inclinometer can be compared thereto.